Fifty-State-Legal Head & Cam Setup Unleashes Dozens Of LS1 Ponies

When CT joined the project car fleet, it was a bone-stock 1999 Camaro SS. After receiving an improved clutch and shifter (May 2009), CARB-legal intake and exhaust components (July 2009), and a full street/road race suspension (November 2009), this SS is no longer your average F-body-but now it's time to really start upping the ante. We're not straying from our promised path to performance, either.

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From the get-go, the intention has been nothing less than a 50-state-legal build in accordance with the demands of the California EPA's Air Resources Board, a governing body that has promulgated easily the strictest emissions regulation system in the United States. Our goal continues to be to show how increased LS1 horsepower can go hand-in-hand with the requirements of even the most strict emissions laws out there. This is clearly an issue that, like it or not, will only become more pertinent in the future, so we're facing it head-on.

The name of the game this issue is heads and cam, and as far as emissions legality goes, this is where things get a bit sticky. GMHTP and related publications have in the past featured builds where aftermarket cylinder heads were swapped on along with a mild cam reckoned to "pass the sniffer test," which basically boils down to one which affords a decent enough idle quality to keep your typical inspection station exhaust sampling equipment happy. Some emission inspection procedures are even weaker and simply go by whether an OBD-II vehicle's MIL lamp is lit on the dash-and we all know that simple tuning tricks can keep this light turned off no matter how wild things are underhood!

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As neither of these approaches is a true measure of actual emissions legality (particularly in regard to how Cali does things), we're blazing a trail not oft followed. Finding a set of CARB-certified cylinder heads was as easy as calling up Air Flow Research for a set of the company's well-proven Mongoose Street Heads, but when it came time to select a camshaft, we hit a snag: nobody, and we mean nobody, sells an aftermarket LS camshaft with a CARB E.O. It's not that aftermarket small-block cams can't meet the requirements of the system; check out the CARB website, and there are E.O.-carrying bumpsticks (albeit few) for TPI and LT1 F-bodies. It would just seem that no company has opted to go through the expense and labor-intensive process of certifying a camshaft for LS engines.

Faced with this bump in the road, we seriously considered leaving the stock cam in place, but decided that although a head-only swap would certainly unlock some ponies, it would ultimately shortchange the overall build. We decided a compromise was in order that, although not technically in absolute lockstep with the letter of the law in California, was best in tune with the spirit thereof (can you tell I went to law school?). We would use a factory camshaft that was original equipment in an equivalent cubic-inch engine of similar model year, and was therefore a virtual certainty to pass CARB certification requirements should someone opt to take it through the motions of the process. The clear choice was the '02-04-spec LS6 camshaft as used in Z06 Corvettes, a bumpstick which offers sizable increases in lift and duration over the stock '99 LS1 cam.

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As the situation is similar with LS intake manifolds-none carry a CARB E.O.-we applied the same reasoning in choosing the GM LS6. The "legality" analysis here is even easier, since 2001-2002 F-bodies had this intake from the factory! We promptly ordered up one of SLP's LS6 Intake Manifold Kits and were ready to get started with the swap, so follow along as we add more 50-state-legal LS1 power. And stay tuned next time for even more drastic increases-check out the aftermarket parts database at www.arb.ca.gov and try to guess what we've got in store!

Inside Chris Wilhelm's minty-fresh 10-second show-and-go '99 Camaro SS. We take a look under the hood and see all the things that makes this 1999 Chevy Camaro SS tick. - GM High-Tech Performance Magazine